Pipe form suspension and stripping unit



July '11, 1950 H, G, HOLSTON 2,515,088

PIPE FORM SUSPENSION AND STRIPPING UNIT Filed July 5, 1947 2 Sheets-Sheet 1 INVENTOR BY MiLTfl/ZAL ATTORNEYS H. G. HOLSTON PIPE FORM SUSPENSION AND STRIPPING UNIT Filed July 5, 1947 Fig.3

15 (-1 g H ii 10 I. MY *Qfj'l 2 Sheets-Sheet 2 r\ 2| M E:

INVENTOR ATTORNEYS Patented July 11, 1950 2.12.? '1 o,

UNITED STATES rms PIPE FORM SUSPENSION AND STRIPPING UNIT Harold G. Holston, Caruthers, Calif. I

; Application July 5,1947, Serial No. 759,026

One object of the present invention is to provide a pipe form suspension'and stripping unit which is operative to facilitate lifting of said form from the pipe machine, and to then easily and quickly strip the form from the pipe therein.

Another object of the invention is to provide a device, as above, which is constructed in such manner that the form can be stripped from the pipe adjacent the pointofmanufacture and there deposited directly on a drying pallet for curing.

It is also an object of the" invention to provide a device operative to strip the form from pipe made from a very wet cement mix; a wet mix producing a better and stronger pipe.

A further object of the invention is to provide a pipe form suspension and stripping unit which is operative, upon unlatching and expansion of the form, to forcefully push the pipe downward while simultaneously pulling upward on the form;

the opposed forces thus assuring of rapid and effective stripping of the form, andwith possible deformation or breaking of the fresh pipe minimized. i T

A further object of theinvention is to provide a practical pipe form suspension and stripping unit, and one which will be exceedingly elfe'ctive;

for the purpose for which it is designed.

' These objects are accomplished by means 'of such structure and relative'arrangementof parts as will fully appear by a'perusal of the following specification and claims. In the drawings: a

Fig. 1 is a front elevation of the device con nected to a pipe form. 1 a

. Fig. 2 is a side elevation ofthe device asinitial 1y engaged with a form, but'before lifting of the same to upright working position and loading of the springs. I

Fig. 3 is a sectional elevation of the device in upright working position with the springs loaded.

Fig. 4 is a similar view but shows the springs as unloaded, with resultant relativesliding motion between the form andthe'fresh'pipe therein. v

Referring now more particularly-to'the characters of reference on the drawings, the device" is adapted for use in connection with the jacket or form used in a pipe making machine for the production of concrete pipe; The form, which indicated generally at l,-is-' of one-piececylindri-J 13 Claims. (01'. 25-1) cal type split vertically for diametrical expansion,

and which expansionis normally prevented by a releasable latching mechanism 2, which includes a hand lever 3 The form I is contracted when in thepipe making machine, and a sectionoffresh concrete' pipe, as at 4, is shaped in the con tracted form'by the machine; the lower end of the section of pipe-seating on a bottom retaining ring which has a configuration to form the male joint, while the'upper end of the pipe section 4* is shaped, as the female joint, by a top ring 5. This'top ring 5 is placed in the form in shaping relation to theupper end of the pipe section 4 after'the'form is removed from the pipe making machine. The top ring 5 includesa cross handle 6 whi-ch'the operator grasps to place said top ring 5; the latter being rotated back and forth by the operator while simultaneously pressed downward,

whereby to properly seat such ring directly on the upper end of said pipe section 4.

After a fresh section 4 of pipe is formed in one of the contracted; cylindrical pipe forms I, and the top ring' 5 seated in place, the form is engaged by the suspension and stripping unit, which forms thesubject of the present invention, and which comprise the following: I

A rigid crossbar I, of slightly greater length than the diameter of the form I, is fitted, at op-"-" posite ends, with rigid depending legs 8 having hooks 9 on their lower ends; said hooks opening upwardlyand being adapted to engage, from below, with lifting trunnions Ill on opposite sides of the form I some distance below the top of the latter."

Centrally. of its ends the cross bar 1 is fitted with a rigid upstanding rod II which projects in relatively 'slidable relation through a central opening [2 in the bottom of an upstanding cage [3. Within the upstanding cage l3 the rod H i is formed witha head [4, and a heavy-duty compression spring l5 engages between the head [4,: and the bottom of said cage.

A cross plate I6'is fixed in connection with the cage l3 above the same,'and includes an up standing projecting eye I! adapted for engage-. mentrbythe'hook' l8 of a hoist cable 19. The hoist (not shown) from which the cable l9 de-. pends is of a type which permits said hoist cable to be swung from a point adjacent the pipe making machine toanother point adjacent a eta tion for pallets upon which the fresh pipe is to. be deposited.

Belowthe .rigid cross bar I the device includesa horizontal shaft 20 parallel to, but spaced from;

:such bar. At its ends the horizontal cross shaft duty compression spring 26 is of such length that it normally extends downwardly to a point adjacent, but short of, the lower end of the sad-= dle 25.

After a contracted and latched'form l is removed from the pipe making machine with a fresh section 4 of pipe therein, and the top ring 5 ,applied, the described suspension and stripping unit is. used in thefollowing manner: I

. The hoist cable l9 is manipulated to bring the device directly over the form, and, with thelegs 8 -stradd1ing the latter, the hooks 9 are engaged with-thelifting trunnions It]. At this stagethe hoist cable I9is at such length that the entire device is on an upward incline, as in Fig. 2.

With the device in this position the saddlei is. manually engaged over the cross handle 6 of the ,top ring 5, as also shown in Fig. 2, and then the hoist, cable 9 is raised until thedevice is erect, at which time the tubularneck 23 passes dead-center slightly and bears against a, stop .29 projecting from the crossbar 6, as in Fig. 3, lockingup this assembly. The tubularneck. 23 is secured to the rotary sleeve 2.21m offset rela tion,-as. shown, to i eilitatesuch passage beyond dead center, and engagement ith the. stop 29, in locked-up position.

The length of the legs 8 is such, that when the device is, erected, as above described, the heavy dutycompression spring 26 is loaded, in themana device lifts the form I 01f the floor, whereupon thew i htof the form,v suspended from the rod Uploads thecomp essicn spring. l5 in the cage. l3. r v

With the form I suspendedoff thefloon'the hoistcable. I9 is manipul ted until said form is,

directly above a pallet onto. which the fresh pipe. section 4 is to be deposited; the lower end of-the form I being only a very short distance above the top of said pallet. l

'With the form so suspended, the hand lever-.315 thrown .in a direction to release. the... latching mechanism, whereupon the form I expands-diametrically to .a considerable extent. .When'this occurs, the loaded springs l5 and 2e, acting in opposition to each other, act to pull upwardly onthe form l and push downwardly on the top ring. 5,.respectively. This resultsinrelative vertical slipping motion of the fresh section 4 of pipe and the then expanded form I; thesection moving downwardly and seating on the pallet, whil the. form slips upwardly. After the initial-slipping motion between. the fresh section v4 of pipe and the .form. l is accoms plished. by the described opposedspring arrange-J ment, the hoist cable I9 is raised tosa'n extent. that said form is entirely stripped off the pipe section 4 in a vertically upward. direction. In the concrete pipe making industry-it has ner, illustrated in Fig. 3, with the force, exerting; downwardly on the. cross handle 6. Thereafter.

451; .with continued raising of the hoist cable. ld' the been the practice heretofore to use a relatively large number of the forms I, and to leave them on the pipe sections 4 until the latter are cured to a considerable degree. This meant that not only uneconomic use of the forms, but the stripping thereof had to take place in the drying yard rather than immediately adjacent the pipe mak-. ing machine. With the device of the present invention, a relatively small number of the forms I is needed, as such forms can be stripped from the pipe sections while fresh and the section deposited onto the pallets adjacent the point of manufacture, Thereafter, the'pallets with the [fresh pipe thereon, and without any surrounding form, travel to the drying yard for curing.

After the form is lifted clear of the fresh section l ofpipe, proper manipulation of the hoist cable l9 returns said'form to adjacent the pipe wet mix is known to produce a better and stronger.

pipe.

While the device is shown and described a used in connection with a split-type, one-piece, diametrically expansible jacket or form, suchdece ha also been. found extremely effective.- tc. strip fresh concretepipefrom a non-split andv non-expansible but. slightly upwardly tapered ype of jacket or form. From the foregoing description it will bereadily seen that there has been produced such a device.

as substantially fulfills. the'obiects ofthe invention, as set forth herein.

While this specification, sets forth in detail the present and preferred;constru0tion of the de-, vice, still in practicesuchdeviations from such. detailmay be resortedtc as. do not form a de-- parture. from, the spirit of the invention, as defined by the appended claims.

Hav n hus descri ed the invention, the fol-. lowing is claimed asnew and useful, and upon which Letters Patent are desired:

the device comprising .a member adapted to be connected to a liftmechanism, means to suspend the form from the membenthetcp ring includ,

ing a r ss andl and eansbetween the mem ber and top ring cross handle :Qperative to urge the fresh pipcsectiondownward'in'the suspended f said means including across shaft mounted in nnection with the memberbelowzthe same and in substantial. parallelism: with the cross. handle, a sleeve on the. cross. shaftrotatable'. about the longitudinal axis of such shaft, a tubular neck fixed on and depending'from the sleeve and having notches on opposite, sides to form a.

saddle which straddles the cross handle, and-5a compressionspring inthe. neck. bearing at. its;

lower end on the cross handle.

.2. A, suspension and stripping device for an upstanding, concrete pipe form having a fresh,--. pipe section releasably-engaged therein, anda ton. ring seated on the upper end of the section; the device comprising a member adapted to be 0011-} nected toa. lift mechanism, means to. suspend the form from. the member, the 'top ring including a crosshandle, and means between the member and top ring cross handle operative to urge the fresh pipe section downward in the suspended form; said means including a cross shaft mounted in connection with the member below the same and in substantial parallelism with the cross handle, a sleeve on the cross shaft rotatable about the longitudinal axis of such shaft, a tubular neck fixed on and depending from the sleev and having. notches onopposite sides to form a saddle which straddles the cross handle, and a compression spring in the neck bearing at its lower end on the cross handle; there being stop means positioned to engage the neck when it passes dead center in one direction.

3. A suspension and stripping device for an upstanding, concrete pipe form havinga fresh pipe section releasably engaged therein, and a top ring seated on the upper end of the section; the device comprising a member adapted. to be connected to a lift mechanism, spaced legs depending from the member adapted to releasably connect with the form on opposite sides to suspend said form, a cross shaft mounted in connection with the member below the same and intersecting the vertical axis of the form, a sleeve on" the' cross shaft rotatable about the longitudinal axis of such shaft, a tubular neck fixed on and depending from the sleeve and having notches on opposite sides to form a saddle, the top ring including a cross handle, the saddle straddling said cross handle, and a compression spring in the neck bearing at its lower end on the cross handle.

4. A suspension and stripping device for an upstanding, concrete pipe form having a fresh pipe section releasably engaged therein, and a top ring seated on the upper end of the section; the device comprising a suspension assembly adapted to connect between a lift mechanism and the form, a pair of springs in said assembly, said springs being loaded when the form is suspended by said assembly and working in opposition; one spring cooperating with and pushing the trip ring downward, and the other spring pulling upward on the form.

5. A suspension and stripping device for an upstanding, concrete pipe form having a fresh pipe section releasably engaged therein, and a top ring seated on the upper end of the section; the

device comprising a cross bar adapted to be con-' nected to a lift mechanism, means to suspend the form from the cross bar, and a spring arranged between the cross bar and top ring in a manner such that the spring is loaded and urges the top ring downward when the form is so suspended.

6. A suspension and stripping device for an upstanding concrete pipe form having a fresh pipe section releasably engaged therein, and a top ring seated on the upper end of the section; the device comprising a cross bar adapted to be connected to a lift mechanism, means to suspend the form from the cross bar, a spring arranged between the cross bar and top ring in a manner such that the spring is loaded and urges the top ring downward when the form is so suspended, and another spring arranged between the cross bar and lift mechanism in a manner to pull upward on the suspended form.

7. A suspension and stripping device for an upstanding, concrete pipe form having a fresh pipe section releasably engaged therein, and a top ring seated on the upper end of the section;

the device comprising a cross bar,.a rod extend-- ing upward from the barintermediate its ends, acage into which the rod. slidably projectsfrom below, a head on the rod in the cage, a compression spring in the cage between the bottom thereof and said head, means to connectthe cage to a lift mechanism, means to suspend the form from the cross bar, and spring means between the cross bar, and top ring pushing downwardon said ring when the .form is so suspended. u I

8. A suspension and stripping device for an upstanding, concrete. pipe form having a fresh pipe section releasably engaged therein, and a top ring seated on the upper end of the section; the device comprising a cross bar, a rod extending upward from the bar intermediate its ends, a cage into which the rod slidably projects from below, a head on the rod in the cage, a compression spring in the cage between the bottom thereof and said head, means to connect the cage to a lift mechanism, means to suspend'the formfrom the cross bar, and spring means between the cross bar and top-ring pushing downward on said ring when'the form is so suspended; the top ring having a cross handle and said spring means working against said handle.

9. A suspension and stripping device for an upstanding, concrete pipe form having a fresh pipe section releasably engaged therein, and a top ring seated on the upper end of the section; the device comprising a cross bar, a rod extend-- ing upward from the bar intermediate its ends, a cage into which the rod slidably projects from below, a head on the rod in the cage, a compression spring in the cage between the bottom thereof and said head, means to connect the cage to a lift mechanism, means to suspend the form from the cross bar, and spring means between the cross bar and top ring pushing downward on said ring when the form is so suspended; said form suspension means being of fixed length, and said spring means bein loaded when said suspension means is substantially upright.

10. A suspension and stripping device for an upstanding, concrete pipe form having a fresh pipe section releasably engaged therein, and a top ring seated on the upper end of the section; the device comprising a cross bar, a rod extending upward from the bar intermediate its ends, a cage into which the rod slidably projects from below, a head on the rod in the cage, a compression spring in the cage between the bottom thereof and said head, means to connect the cage to a lift mechanism, means to suspend the form from the cross bar, and spring means between the cross bar and top ring pushing downward on said ring when the form is so suspended; said form suspension means being spaced legs adapted to detachably connect to opposite sides of the form, and said spring means including a depending tubular neck notched on opposite sides at its lower end to form a saddle, the top ring having a cross handle and the saddle straddling the same, and a compression spring in the neck lpaded when the suspension means is upright and then bearing on the cross handle.

11. A suspension and stripping device for an upstanding, concrete pipe form having a fresh pipe section releasably engaged therein, and a top ring seated on the upper end of the section; the device comprising a cross bar intersecting the vertical axis of the form, a rod extending upward from the bar intermediate its ends, a cage into which the rod slidably projects from below, a head on the rod in the cage, a compression spring in the cage between the bottom thereof and said names head;..means .to connect the cage-to a-iiftimecha nism; means to: suspend the form: fromthe: cross bar, a cross shaft mounted: Connection with th'etcross bar below thesameand in substantial parallelism: with said cross bar; a; sleeve on the cross shaft rotatable about the Iongitudina'laxis of said shait; a tubular neck fixed on-and projecting downwardfrom the rotary sleeve, said neck being notched on opposite sides at its lower endto form a saddle, the top ring having at cross: handleand the saddle straddling thersame, and a compressionspringtin the; neck loaded when the suspension. means is'upright and then bearing on. the cross. handle.

12i1A. suspension: andflstripping device for an upstanding, concrete pipe form having a fresh pipe: section releasably engaged therein. and; a topring seateden the upper end. of the section; thedevicecomprising a cross bar, a rod extendingupward'from. the bar intermediate its ends, a cage into which the rod slidably' projects from below, a head on the rodin the cage, a compressionxspring' in the cage" between the bottom thereof and said'head, means to connect the cage toaliit mechanism, means to suspend the form from the cross bar, said suspension means" including transversely spaced. legs adapted to detaeh'ably connect to-oppo'site sides of the form,

and-spring meansbetweenthe-eross bsfiand'td's ring pushing: downward .011 Said ring." when the form is so su'spended.

13; A suspension and stripping unit for com cnete pipe form com'prising -a cross bar; species! suspension legs depending from thebar h60l s the lower: ends: of the legs a rod extending up ward nomthe bar" intermediate its ends, acag'e into" which the rod slidably projects fromabelow, a headnon the rod in the cage, a compression spring in the cage between the" bottom thereof and said head, an eye'on" top ofrthe'cage, a GI'OSS' shalt mounted in. connection with the; crossv bar below the same, a rotaryv sleeve on the. cross'ishaft; a tubular neck fixed on and projecting. downward from the rotary sleeve, said. neck being notched on opposite sides at its'lower end to form a saddle, and a compression spring in the neck extending downward into the saddle.

HAROLD G: HQLSTONL REFERENCES CITED The fol-lowing" references are of re'eordvm: the file of this patent:

UNITEDSTATES PATENTS Number Name Date;

1,859,191 Almquist 1 i May 117, 1932 

